Why does PLA warp or elephant-foot on a hot bed?

Set the bed from the row, then read the comment as a comment. PLA temperature, warping, bed adhesion, and PLA prints are the guides. Elephant foot is not what these five threads document.

The beds on the rows

Bambu PLA Basic lists a bed of 35–45 °C (95–113 °F) and a nozzle of 190–230 °C (374–446 °F). Prusament PLA lists 40–60 °C (104–140 °F) and 205–225 °C (401–437 °F) in the catalog. The Jet Black page lists a heatbed of 50–60 °C (122–140 °F) and a nozzle of 215 °C (419 °F). PolyLite PLA lists 25–60 °C (77–140 °F) and 190–230 °C (374–446 °F). ELEGOO PLA lists 35–65 °C (95–149 °F) and 190–230 °C (374–446 °F). PLA is the hub.

The lift, and the hot box

r/FixMyPrint 1hym5rs is an Ender 3 and PLA+. One side lifts. The title says the bed is 50f and the nozzle is 200f. The score-53 comment says the writer probably means 50 °C (122 °F), that a real 50 °F bed is far too low, that even 50 °C (122 °F) is slightly low for PLA, and that 60 or 65 can work. It also says keep drafts and overnight temperature swings off the printer. A score-10 comment says the long straight corner is cooling unevenly and mentions a draft shield or a wide brim. 60 and 65 are the comment. They sit above the Bambu PLA Basic bed. 65 sits above the Prusament and PolyLite beds. 65 is the top of the ELEGOO PLA bed.

r/3Dprinting 105by21 is an Ender 5 Plus. The same print looks fine with the Creality enclosure open and under-extrudes with it zipped, at nozzle 200 and bed 50, and the title says Celsius. The score-25 comment says PLA is soft and the closed box let the extruder chew it. The score-13 comment says PLA has to cool and the enclosure is for ABS or PETG. The score-9 comment calls it heat creep, a mini oven softening the PLA before the nozzle. A score-7 comment says a cold garage can need the box. The bed in the title is 50 °C (122 °F). The failure they describe is the air around the printer.

Three threads about something else

r/FixMyPrint vmmrlq is a rough surface at a 200 nozzle and a 60 bed. The score-29 comment says clog, moisture, or not enough extrusion, and says retune if you changed settings. A score-19 comment hears popping. A score-5 comment says heavy retraction can pull air, and wet filament can pop too. Drying is the moisture page. 60 is the post's bed. The comment does not call it too hot.

r/FixMyPrint vx5cn4 clicks, extrudes less, at extruder 211 and bed 55. The score-23 comment says a partial clog and says try 230. The score-8 comment says the nozzle may be too close to the bed. 230 and 55 are the thread. Clogs is that failure.

r/FixMyPrint 117fwds is PETG at 240 °C (464 °F). One photo is a 70 °C (158 °F) bed. The last is a 90 °C (194 °F) bed. The score-12 comment says cool the part evenly and kill drafts. A score-10 comment never runs the fan on PETG. PETG and warping are those pages. The material is not PLA.

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